Using an uniform protocol designed by World Health Organization, neuro-epidemiologic investigations have been carried out in the United States, Nigeria, People's Republic of China; smaller pilot studies have been conducted in Chile, Colombia, Ecuador, India, Mexico, Italy, Senegal, Spain, Venezuela. To exchange the information and analyze the data from different studies are necessary. Among the various investigations, the study in China has the largest sample population (more than 300,000 inhabitants from 7 cities and 22 rural communities in 21 provinces have been investigated door-to-door). The reported results of this study elicited considerable interest among a great number of neurologists and epidemiologists internationally. They requested the opportunity to observe the work in China and compare the findings with those of their own investigations. Major Program of the symposium: a) Methodology of neuroepidemiology: descriptive, analytic, and experimental studies; b) Clinical applications: epidemiology of different neurologic disorders focus on cerebrovascular disease, epilepsy, brain tumor, head injury, etc.; c) Geographic epidemiology: distribution of neurologic disorders in North and South America, Africa, Asia, Australia, and Europe. In each day there will be didactic presentations in the morning and workshop session in the afternoon. Proceedings of the meeting in English and Chinese will be published respectively.